The Interpet Airvolution Air Pump AV2 will power an undergravel filter up to 91.5cm in length, or one 46cm airwall, or four ornaments. It is a small pump with a long, reliable, high performance and features inlet and outlet noise suppression as well as a quality moulded case and to absorb sound with anti-vibration feet. The primary fine white and secondary carbon filter ensures clean air for your aquarium.